Toughened cyanoacrylate compositions

ABSTRACT

The present invention relates to toughened cyanoacrylate compositions.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to toughened cyanoacrylate compositions.

2. Brief Description of Related Technology

Cyanoacrylate compositions are well known as one component reactiveadhesives, which are quick bonding and suitable for applications onvariety of substrates. See H. V. Coover, D. W. Dreifus and J. T.O'Connor, “Cyanoacrylate Adhesives” in Handbook of Adhesives, 27,463-77, I. Skeist, ed., Van Nostrand Reinhold, New York, 3rd ed. (1990).See also G. H. Millet, “Cyanoacrylate Adhesives” in StructuralAdhesives: Chemistry and Technology, S. R. Hartshorn, ed., Plenun Press,New York, p. 249-307 (1986).

U.S. Pat. No. 4,440,910 (O'Connor) pioneered rubber toughenedcyanoacrylate compositions through the use of certain organic polymersas toughening additives that are elastomeric, i.e., rubbery, in nature.The '910 patent is thus directed to and claims a curable adhesivecomprising a substantially solvent-free mixture of: (a) a cyanoacrylateester, and (b) about 0.5% to about 20% by weight of an elastomericpolymer. The elastomeric polymer is selected from elastomeric copolymersof a lower alkene monomer and (i) acrylic acid esters, (ii) methacrylicacid esters or (iii) vinyl acetate. More specifically, the '910 patentnotes that as toughening additives for cyanoacrylates, acrylic rubbers;polyester urethanes; ethylene-vinyl acetates; fluorinated rubbers;isoprene-acrylonitrile polymers; chlorosulfonated polyethylenes; andhomopolymers of polyvinyl acetate were found to be particularly useful.

The elastomeric polymers are described in the '910 patent as eitherhomopolymers of alkyl esters of acrylic acid; copolymers of anotherpolymerizable monomer, such as lower alkenes, with an alkyl or alkoxyester of acrylic acid; and copolymers of alkyl or alkoxy esters ofacrylic acid. Other unsaturated monomers which may be copolymerized withthe alkyl and alkoxy esters of acrylic include dienes, reactivehalogen-containing unsaturated compounds and other acrylic monomers suchas acrylamides.

One group of elastomeric polymers are copolymers of methyl acrylate andethylene, manufactured by DuPont, under the name of VAMAC, such as VAMACN123 and VAMAC B-124. VAMAC N123 and VAMAC B-124 are reported by DuPontto be a master batch of ethylene/acrylic elastomer.

Henkel Corporation (as the successor to Loctite Corporation) has soldfor a number of years since the filing of the '910 patent rubbertoughened cyanoacrylate adhesive products under the tradename BLACK MAX,which employ as the rubber toughening component the DuPont materialscalled VAMAC B-124 and N123. In addition, Henkel has sold in the pastclear and substantially colorless rubber toughened cyanoacrylateadhesive products, namely, LOCTITE 4203, 4204 and 4205, which employ asthe rubber toughening component the DuPont material, VAMAC G.

Notwithstanding the state of the art, it would be desirable to providealternative toughened cyanoacrylates for a number of reasons, includingproviding the end user with additional product choices, hedging againstraw material supply interruptions or shortages, or regulatoryrequirements that hampers widespread usage of certain raw materials.

SUMMARY OF THE INVENTION

The present invention is directed to a toughened cyanoacrylatecomposition which includes, beyond the cyanoacrylate component, a ketonecontaining material component, such as one within the followingstructures:

where ′R is

and R is linear or branched C₁ to C₇ alkyl, C₂ to C₇ alkenyl, or C₃ toC₇ cycloalkyl or cycloalkenyl, interrupted or substituted by carbonylfunctionality and/or functionalized with a C₁ to C₃ alkoxy group;

where R is linear or branched C₁ to C₇ alkyl, C₂ to C₇ alkenyl, or C₃ toC₇ cycloalkyl or cycloalkenyl, interrupted or substituted by carbonylfunctionality and/or functionalized with a C₁ to C₃ alkoxy group, and R*is H, methyl, or ethyl. In these structures, m, n and p together equal100 percent. More specifically, m and n are each between 7 and 15percent and together are between 17.5 and 26 percent. Of course, prepresents that percent value substrated from 100 percent.

Particularly desirable ketone containing materials according to thesestructures include terpolymers of carbon monoxide, unsaturated ester(e.g., a vinylester or an ester of an unsaturated acid) and ethylene,for instance poly(ethylene-co-vinylacetate-co-carbon monoxide)(“PEVACO”), such as is available commercially from Aldrich or DuPontunder the tradename ELVALOY 741, ELVALOY 742 and ELVALOY 4924; andpoly(ethylene-co-butylacrylate-co-carbon monoxide) (also known as abutylacrylate/ethylene/carbon monoxide co-polymer, “BAECO”), such as isavailable commercially from Aldrich or DuPont under the tradenamesELVALOY HP661, ELVALOY HP662 and ELVALOY HP771; and homopolymers of avinylketone, such as poly(methylvinylketone) (“PMVK”).

In another aspect, the present invention is directed to a method ofbonding two or more substrates including the steps of providing at leasttwo substrates; applying, onto at least a portion of a surface of one orboth of the at least two substrates, a cyanoacrylate composition asnoted above; contacting the surfaces of the at least two substrateshaving the cyanoacrylate composition therebetween; and curing thecyanoacrylate composition.

In still another aspect, the present invention is directed to a bondedassembly including: a first substrate having a first surface; anothersubstrate having a second surface; and a cured cyanoacrylate compositiondisposed between the first and second surfaces, the composition havingincluded prior to cure: a cyanoacrylate component and the polymercomponent as noted above.

In yet another aspect, the present invention is directed to a method ofpreparing the cyanoacrylate composition as noted above.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to a toughened cyanoacrylatecomposition, which includes, beyond the cyanoacrylate component, aketone containing material.

The cyanoacrylate component includes at least one α-cyanoacrylatemonomer of the formula:

where R¹ represents a straight chain or branched chain alkyl grouphaving 1 to 12 carbon atoms (which may be substituted with a substituentsuch as a halogen atom or an alkoxy group), a straight chain or branchedchain alkenyl group having 2 to 12 carbon atoms, a straight chain orbranched chain alkynyl group having 2 to 12 carbon atoms, a cycloalkylgroup, an aralkyl group or any aryl group. Specific examples of R¹ are amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a pentyl group, a hexyl group, anallyl group, a methallyl group, a crotyl group, a propargyl group, acyclohexyl group, a benzyl group, a phenyl group, a cresyl group, a2-chloroethyl group, a 3-chloropropyl group, a 2-chlorobutyl group, atrifluoroethyl group, a 2-methoxyethyl group, a 3-methoxybutyl group anda 2-ethoxyethyl group. Ethyl cyanoacrylate is a particularly desirablechoice for use in the inventive compositions.

A single α-cyanoacrylate monomer or a mixture of two or more of theseα-cyanoacrylate monomers can be used. Generally, the aboveα-cyanoacrylate monomer used alone as an adhesive, and one or morecomponents such as those set forth below, are used to formulate acommercial composition. The additional components includes, but are notlimited to, accelerators; anionic polymerization inhibitors; radicalpolymerization inhibitors; additives, such as plasticizers, heatstabilizers and toughening agents; and/or perfumes, dyes, and pigments.

A suitable amount of α-cyanoacrylate monomer present in the inventivecompositions is from about 50 to 99.5% by weight, such as 60 to 95% byweight, desirable 85% by weight, based on the total weight of thecomposition.

The ketone containing material may be within the following structures:

where ′R is

and R is linear or branched C₁ to C₇ alkyl, C₂ to C₇ alkenyl, or C₃ toC₇ cycloalkyl or cycloalkenyl, interrupted or substituted by carbonylfunctionality and/or functionalized with a C₁ to C₃ alkoxy group;

where R is linear or branched C₁ to C₇ alkyl, C₂ to C₇ alkenyl, or C₃ toC₇ cycloalkyl or cycloalkenyl, interrupted or substituted by carbonylfunctionality and/or functionalized with a C₁ to C₃ alkoxy group, and R*is H, methyl, or ethyl. In these structures m and n are each between 7and 15 percent and together are between 17.5 and 26 percent. Of course,p represents that percent value subtracted from 100 percent.

Particularly desirable ketone containing material according to thesestructures include those prepared from terpolymers of carbon monoxide,unsaturated ester (e.g., a vinylester or an ester of an unsaturatedacid) and ethylene, for instance poly(ethylene-co-vinylacetate-co-carbonmonoxide) (“PEVACO”), such as is available commercially under thetradenames ELVALOY 741, ELVALOY 742 and ELVALOY 4924; andpoly(ethylene-co-butylacrylate-co-carbon monoxide) (also known asbutylacrylate/ethylene/carbon monoxide co-polymer, “BAECO”), such as isavailable commercially under the tradenames ELVALOY HP661, ELVALOY HP662and ELVALOY HP771; and homopolymers of a vinylketone, such aspoly(methylvinylketone) (“PMVK”).

The ketone containing material should be used in the present inventionin amounts of about 0.5% to about 30%, for instance about 2.5% to about20%, such as about 5% to about 15%, by weight based on the total weightof the composition.

An anionic polymerization inhibitor is generally added toα-cyanoacrylate compositions in an amount from about 0.0001 to 10% byweight based on the total weight of the composition, to increase thestability of the composition during storage. Examples of usefulinhibitors include sulfur dioxide, sulfur trioxide, nitric oxide,hydrogen fluoride, organic sultone inhibitors, boron trifluoride andmethane sulfonic acid, aromatic sulfonic acids, aliphatic sulfonicacids, and sulfones. The amount of inhibitor will suitably be anyconvenient amount in order to slow down cure of the composition.Desirably, inhibitors of anionic polymerization are present at about0.0001% to about 0.1% by weight based on the total weight of thecomposition.

A radical polymerization inhibitor is generally added to α-cyanoacrylatecompositions as well, in an amount from about 0.001 to 2.0%,particularly 0.03 to 0.5%, based on the total weight of the composition,for the purpose of capturing radicals which are formed by light duringstorage. Such inhibitors are ordinarily of the phenolic type include,for example, hydroquinone and hydroquinone monomethyl ether. Otherinhibitors suitable for use herein include butylated hydroxytoluene andbutylated hydroxyanisole.

A thickener may be added to increase the viscosity of theα-cyanoacrylate composition. Various polymers can be used as thickeners,and examples include poly(methyl methacrylate) (“PMMA”), poly(ethylmethacrylate) (“PEMA”), methacrylate-type copolymers, acrylic rubbers,cellulose derivatives, polyvinyl acetate and poly(α-cyanoacrylate). Asuitable amount of thickener is generally about 0.01 to 30% by weight,preferably 5.0 to 25% by weight, based on the total weight of thecyanoacrylate composition.

Plasticizers may also be added to the cyanoacrylate component to furtheraid in durability and impact, heat, and moisture resistance. Theplasticizer is preferably present in an amount of about 0.05% to about25%, more preferably about 1% to about 15%, such as about 5% to about10%, by weight based on the total weight of the composition.

Perfumes, dyes, pigments, and the like may be added to the inventivecomposition depending on use purposes in amounts which do not adverselyaffect the stability of the α-cyanoacrylate monomer. The use of suchadditives is within the skill of those practicing in the cyanoacrylateadhesive art and need not be detailed herein.

Accelerators that may be useful in the cyanoacrylate compositionsinclude for example calixarenes, oxacalixarenes, and combinationsthereof. Of the calixarenes and oxacalixarenes, many are known, and arereported in the patent literature. See e.g. U.S. Pat. Nos. 4,556,700,4,622,414, 4,636,539, 4,695,615, 4,718,966, and 4,855,461, thedisclosures of each of which are hereby expressly incorporated herein byreference.

Another potentially useful accelerator component is a crown ether. Ahost of crown ethers are known. For instance, examples which may be usedherein either individually or in combination, or in combination with thecalixarenes and oxacalixarenes described above include 15-crown-5,18-crown-6, dibenzo-18-crown-6, benzo-15-crown-5, dibenzo-24-crown-8,dibenzo-30-crown-10, tribenzo-18-crown-6, asym-dibenzo-22-crown-6,dibenzo-14-crown-4, dicyclohexyl-18-crown-6, dicyclohexyl-24-crown-8,cyclohexyl-12-crown-4, 1,2-decalyl-15-crown-5, 1,2-naphtho-15-crown-5,3,4,5-naphthyl-16-crown-5, 1,2-methyl-benzo-18-crown-6,1,2-methylbenzo-5, 6-methylbenzo-18-crown-6, 1,2-t-butyl-18-crown-6,1,2-vinylbenzo-15-crown-5, 1,2-vinylbenzo-18-crown-6,1,2-t-butyl-cyclohexyl-18-crown-6, asym-dibenzo-22-crown-6 and1,2-benzo-1,4-benzo-5-oxygen-20-crown-7. See U.S. Pat. No. 4,837,260(Sato), the disclosure of which is hereby expressly incorporated here byreference.

Other suitable accelerators include those described in U.S. Pat. No.5,312,864 (Wenz), which are hydroxyl group derivatives of an α-, β- orγ-cyclodextrin which is at least partly soluble in the cyanoacrylate; inU.S. Pat. No. 4,906,317 (Liu), which are silacrown compounds toaccelerate fixturing and cure on de-activating substrates such as wood,examples of which are within the following structure:

where R³ and R⁴ are organo groups which do not themselves causepolymerization of the cyanoacrylate monomer, R⁵ is H or CH₃ and n is aninteger of between 1 and 4. Examples of suitable R³ and R⁴ groups are Rgroups, alkoxy groups such as methoxy, and aryloxy groups such asphenoxy. The R³ and R⁴ groups may contain halogen or other substituents,an example being trifluoropropyl. However, groups not suitable as R⁴ andR⁵ groups are basic groups such as amino, substituted amino andalkylamino.

Specific examples of silacrown compounds useful in the inventivecompositions include:

dimethylsila-11-crown-4;

dimethylsila-14-crown-5; and

dimethylsila-17-crown-6.

The accelerator component should be included in the compositions in anamount within the range of from about 0.1% to about 10%, with the rangeof about 0.5% to about 5% being desirable, and about 0.1% to about 1% byweight based on the total weight of the composition being particularlydesirable. See e.g. U.S. Pat. Nos. 4,170,585; 4,450,265; 6,294,629; and6,475,331, the contents of which are all incorporated herein byreference.

It may also be desirable to co-toughen the inventive composition with asecondary co-toughening component, such as those disclosed in U.S. Pat.No. 4,440,910 (O'Connor), which pioneered rubber toughened cyanoacrylatecompositions through the use of certain organic polymers as tougheningadditives that are elastomeric, i.e., rubbery, in nature. The '910patent is thus directed to and claims a curable adhesive comprising asubstantially solvent-free mixture of: (a) a cyanoacrylate ester, and(b) about 0.5% to about 20% by weight of an elastomeric polymer. Theelastomeric polymer is selected from elastomeric copolymers of a loweralkene monomer and (i) acrylic acid esters, (ii) methacrylic acid estersor (iii) vinyl acetate. More specifically, the '910 patent notes that astoughening additives for cyanoacrylates, acrylic rubbers; polyesterurethanes; ethylene-vinyl acetates; fluorinated rubbers;isoprene-acrylonitrile polymers; chlorosulfonated polyethylenes; andhomopolymers of polyvinyl acetate were found to be particularly useful.

The elastomeric polymers are described in the '910 patent as eitherhomopolymers of alkyl esters of acrylic acid; copolymers of anotherpolymerizable monomer, such as lower alkenes, with an alkyl or alkoxyester of acrylic acid; and copolymers of alkyl or alkoxy esters ofacrylic acid. Other unsaturated monomers which may be copolymerized withthe alkyl and alkoxy esters of acrylic include dienes, reactivehalogen-containing unsaturated compounds and other acrylic monomers suchas acrylamides.

One group of elastomeric polymers are copolymers of methyl acrylate andethylene, manufactured by DuPont, under the name of VAMAC, such as VAMACN123 and VAMAC B-124. VAMAC N123 and VAMAC B-124 are reported by DuPontto be a master batch of ethylene/acrylic elastomer.

Henkel Corporation (as the successor to Loctite Corporation) has soldfor a number of years since the filing of the '910 patent rubbertoughened cyanoacrylate adhesive products under the tradename BLACK MAX,which employ as the rubber toughening component the DuPont materialscalled VAMAC B-124 and N123. Thus, these DuPont materials may be used toco-toughen the inventive composition. In addition, Henkel has sold inthe past clear and substantially colorless rubber toughenedcyanoacrylate adhesive products, namely, LOCTITE 4203, 4204 and 4205,which employ as the rubber toughening component the DuPont material,VAMAC G. VAMAC G may be used to co-toughen the inventive composition, aswell.

VAMAC VCS rubber appears to be the base rubber, from which the remainingmembers of the VAMAC product line are compounded. VAMAC VCS is areaction product of the combination of ethylene, methyl acrylate andmonomers having carboxylic acid cure sites, which once formed is thensubstantially free of processing aids such as the release agentsoctadecyl amine, complex organic phosphate esters and/or stearic acid,and anti-oxidants, such as substituted diphenyl amine.

Recently, DuPont has provided to the market under the trade designationVAMAC VMX 1012 and VCD 6200, which are rubbers made from ethylene andmethyl acrylate. It is believed that the VAMAC VMX 1012 rubber possesseslittle to no carboxylic acid in the polymer backbone. Like the VAMAC VCSrubber, the VAMAC VMX 1012 and VCD 6200 rubbers are substantially freeof processing aids such as the release agents octadecyl amine, complexorganic phosphate esters and/or stearic acid, and anti-oxidants, such assubstituted diphenyl amine, noted above.

The inventive composition may be co-toughened with a rubber tougheningcomponent having (a) reaction products of the combination of ethylene,methyl acrylate and monomers having carboxylic acid cure sites, (b)dipolymers of ethylene and methyl acrylate, and combinations of (a) and(b), which once the reaction products and/or dipolymers are formed arethen substantially free of processing aids, such as the release agentsoctadecyl amine (reported by DuPont to be available commercially fromAkzo Nobel under the tradename ARMEEN 18D), complex organic phosphateesters (reported by DuPont to be available commercially from R.T.Vanderbilt Co., Inc. under the tradename VANFRE VAM), stearic acidand/or polyethylene glycol ether wax, and anti-oxidants, such assubstituted diphenyl amine (reported by DuPont to be availablecommercially from Uniroyal Chemical under the tradename NAUGARD 445).Commercial examples of such rubber tougheners include VAMAC VMX 1012 andVCD 6200 rubbers, and these may be used too.

Preparation of the compositions and products of the present inventioncan be achieved by mixing the polyketone material into the cyanoacrylatecomposition at room temperature. Mixing is performed for a timesufficient to disperse or dissolve the polyketone material into thecyanoacrylate composition, which can vary depending on the batch size.Generally, only seconds or minutes are required to achieve the desiredblending in of the polymer material.

The cyanoacrylate compositions of the present invention are useful inbonding two or more substrates. A sufficient portion of the compositionmay be placed on a surface of one of the two or more substrates. Theother substrate is then positioned adjacent to the cyanoacrylatecomposition and the two substrates are placed in contact to form anassembly, upon curing of the cyanoacrylate.

The following non-limiting examples are intended to further illustratethe present invention.

EXAMPLES

Referring to Tables 1A-1C below, cyanoacrylate compositions labeledSample Nos. 1-21 were prepared by incorporating into the specifiedcyanoacrylate the respective amounts indicated of toughening agent andthickener, with mixing for a period of time of about 0.5 to 1 hour at atemperature of about 50-85° C. The samples were also stabilized at theparts per million (“ppm”) level with acid stabilizers and free radicalstabilizers. EtCA represents ethyl-2-cyanoacrylate; MeCA representsmethyl cyanoacrylate; and MeOEtCA representsmethoxyethyl-2-cyanoacrylate.

TABLE 1A Components Sample No./Amt. (wt. %) Type Identity 1 2 3 4 5 6 78 CA EtCA Bal. — — Bal. Bal. Bal. Bal. Bal. MeCA — Bal. — — — — — —MeOEtCA — — Bal. — — — — — Toughening PEVACO — — — 10 10 — — — AgentBAECO — — — — — 8 10 — ELVALOY — — — — — — — 8.5 HP662 Thickener PMMA —— — — 3 — — —

TABLE 1B Components Sample No. /Amt. (wt. %) Type Identity 9 10 11 12 1314* 15 16 17 18 CA EtCA Bal. Bal. Bal. Bal. — — — — — — MeCA — — — —Bal. — — — — — MeOEtCA — — — — — Bal. Bal. Bal. Bal. Bal. TougheningELVALOY — 8.5 — — — — — — — 8.5 Agent HP771 ELVALOY 8 — — — — — — — — —HP742 PVMK — — 7.5 10 10 — — — — — ELVALOY — — — — — — 8 8.5 10 — HP662ELVALOY — — — — — 8 — — — — HP661 Thickener PMMA — — — — — 6 8 — 5 —*contains 150 ppm of the adhesion promoter, itaconic anhydride

TABLE 1C Components Sample No./Amt. (wt. %) Type Identity 19 20 21* CAMeOEtCA Bal. Bal. Bal. Toughening ELVALOY 8.5 10 — Agent HP771 ELVALOY —— 8 HP4924 Thickener PMMA —  5 6 PEMA 4.0 — — *contains 150 ppm of theadhesion promoter, itaconic anhydride

Below in Tables 2A-2B are data for fixture time and T peel strength(room temperature and after heat ageing) captured for the samples setforth in Tables 1A-1C.

TABLE 2A Sample No. Physical Properties 1 2 3 4 5 6 7 8 9 10 11 FixtureTime (Secs) EDPM 15 15 20 45 45 35 40 30 30 30 30 T Peel Strength(N/mm²) Aluminum 0.2 0.2 0.3 2.0 1.2 — — — — — — Steel [mild] 0.4 0.20.2 1.6 3.8 1.5 1.6 1.1 1.0 1.0 1.0 T Peel Strength Aluminum 0.0 — 0.01.0 — — — — 1.0 — — 2hrs @ 150° C. (N/mm²) Steel [mild] 0.0 — 0.0 1.3 —1.0 1.5 — 1.2 — —

TABLE 2B Sample No. Physical Properties 12 13 14 15 16 17 18 19 20 21Fixture Time (Secs) EDPM 22 40 35 30 45 30 40 25 35 35 T Peel Strength(N/mm²) Aluminum 1.3 — — — 2.3 — 2.5 1.8 — — Steel [mild] 3.0 1.0 3.02.1 2.3 1.7 2.3 1.4 1.7 4.3 T Peel Strength Aluminum — — 1.2 — — — — — —1.0 2 hrs @ 150° C. (N/mm²) Steel [mild] — — 1.0 — — — — — — 1.0

In Tables 2A and 2B, fixture time on EPDM rubber and T peel strength onaluminum and mild steel for cyanoacrylate compositions prepared withseveral different polyketone tougheners on both aluminum and steelsubstrates are reported.

The results set forth in Tables 2A and 2B indicate that fixture times onEPDM rubber were modestly higher, though within the commerciallyacceptable working range, for the inventive compositions as comparedwith compositions without the inventive toughener. As regards T peelstrength, measurements were made at room temperature and after two hoursof heat ageing at a temperature of 150° C. The substrates used in the Tpeel strength evaluation were either aluminum or mild steel. Improvedresults were observed for the inventive composition at room temperatureand after heat ageing.

In Table 3 below, cyanoacrylate compositions labeled Sample Nos. 22-33were prepared to evaluate the polyketone tougheners used in theinventive composition as contrasted to other tougheners and thepolyketone tougheners as used in combination with such other tougheners.Each of these samples was stabilized at the PPM level with added acidicstabilizer.

TABLE 3 Sample No. (wt. %) Physical Properties 22 23 24 25 26 27 28 2930 31 32 33 CA EtCA Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal. — — — —MeOEtCA — — — — — — — — Bal. Bal. Bal. Bal. Allyl CA — — — 40 — — — — —— — — Toughening BAECO 6.0 — — — — — 6.0 — — — — — Agent PEVACO 8.0 6.06.0 6.0 6.0 6.0 — 6.25 — — — — VAMAC 2.0 4.0 2.0 2.0 2.0 2.0 2.0 2.0 — —2.0 2.0 VCS 5500 ELVALOY — — — — — — — — 8.5 — — — HP662 ELVALOY — — — —— — — — — 8.5 6.0 6.0 HP771 Thickener PMMA — — — — 2.5 0.5 — — — — — 1.0Curing Calixarene 0.4 0.4 0.3 0.3 2.5 — 0.4 — — — — — Accelerator Crown— — — — 0.2 0.2 — 0.12 0.12 0.12 0.12 0.12 Ether

Below in Table 4 are data for fixture time and T peel strength capturedfrom the samples set forth in Table 3.

TABLE 4 Sample No. Physical properties 22 23 24 25 26 27 28 29 30 31 3233 Fixture Time EPDM 70 80 70 50 75 80 60 50 45 50 60 60 (Secs) T PeelAluminum 2.2 2.1 3.0 2.2 1.7 1.6 1.5 2.0 2.3 2.5 2.5 2.1 Strength Steel[mild] 2.8 1.8 2.2 1.1 1.3 1.4 1.2 1.8 2.3 2.3 1.5 1.0 (N/mm²)

The results in Table 4 indicate among other things that the use of theco-toughener VAMAC VCS 5500 in the cyanoacrylate composition with PEVACOand without added thickener, demonstrated a T peel strength on aluminumof over 2.0 N/mm² in each measured instance.

1. A cyanoacrylate composition comprising: at least one α-cyanoacrylate;and a polyketone material within the following structure:

wherein ′R is

R is linear or branched C₁ to C₇ alkyl, C₂ to C₇ alkenyl, or C₃ to C₇cycloalkyl or cycloalkenyl, interrupted or substituted by carbonylfunctionality and/or functionalized with a C₁ to C₃ alkoxy group; andthe sum of m, n and p is 100 percent.
 2. The composition of claim 1,wherein said polyketone material is a member selected from the groupconsisting of terpolymers of carbon monoxide, unsaturated ester andethylene; and poly(ethylene-co-butylacrylate-co-carbon monoxide).
 3. Thecomposition of claim 1, wherein said polyketone material ispoly(ethylene-co-vinylacetate-co-carbon monoxide).
 4. The composition ofclaim 1, wherein said polyketone material is present in an amountsufficient to toughen said composition once cured.
 5. The composition ofclaim 1, wherein the α-cyanoacrylate is represented by compounds of theformula:

wherein R¹ represents a straight chain or branched chain substituted orunsubstituted alkyl group having 1 to 12 carbon atoms, a straight chainor branched chain substituted or unsubstituted alkenyl group having 2 to12 carbon atoms, a straight chain or branched chain substituted orunsubstituted alkynyl group having 2 to 12 carbon atoms, a substitutedor unsubstituted cycloalkyl group, an substituted or unsubstitutedaralkyl group or a substituted or unsubstituted aryl group.
 6. Thecomposition of claim 5, wherein R¹ is selected from the group consistingof a methyl group, an ethyl group, an n-propyl group, an isopropylgroup, an n-butyl group, an isobutyl group, a pentyl group, a hexylgroup, an allyl group, a methallyl group, a crotyl group, a propargylgroup, a cyclohexyl group, a benzyl group, a phenyl group, a cresylgroup, a 2-chloroethyl group, a 3-chloropropyl group, a 2-chlorobutylgroup, a trifluoroethyl group, a 2-methoxyethyl group, a 3-methoxybutylgroup, a 2-ethoxyethyl group and combinations thereof.
 7. Thecomposition of claim 1, wherein said α-cyanoacrylate is an ethylcyanoacrylate monomer.
 8. The composition of claim 1, further comprisinga thickener.
 9. The composition of claim 1, wherein said polyketonematerial is present in amounts of about 0.5% to about 30% by weight ofthe composition.
 10. The composition of claim 1, wherein saidα-cyanoacrylate compound comprises an ethyl cyanoacrylate monomer andsaid polyketone material comprisespoly(ethylene-co-vinylacetate-co-carbon monoxide).
 11. The compositionof claim 1, further comprising a co-toughener.
 12. The composition ofclaim 11, wherein the co-toughener is a member selected from the groupconsisting of acrylic rubbers; polyester urethanes; ethylene-vinylacetates; fluorinated rubbers; isoprene-acrylonitrile polymers;chlorosulfonated polyethylenes; homopolymers of polyvinyl acetate; andreaction products of the combination of ethylene, methyl acrylate andmonomers having carboxylic acid cure sites, which once formed are thensubstantially free of processing aids and anti-oxidants; andcombinations thereof.
 13. A cyanoacrylate composition comprising: atleast one α-cyanoacrylate; and a ketone containing material within thefollowing structure:

wherein R is linear or branched C₁ to C₇ alkyl, C₂ to C₇ alkenyl, or C₃to C₇ cycloalkyl or cycloalkenyl, interrupted or substituted by carbonylfunctionality and/or functionalized with a C₁ to C₃ alkoxy group; R* isH, methyl, or ethyl; and n is 100 percent.